AC coupled battery system

[AE-NMidlands]

Let's hope the fuses are up to scratch! That lot will give a fair few kWhr in an instant if there is a short...

[Stinsy]

Let's hope the fuses are up to scratch! That lot will give a fair few kWhr in an instant if there is a short...

Modern batteries have pretty effective overcurrent protection! In fact this can be a problem with some inverters and smaller battery stacks. Charging the capacitors in the inverter trips the inbuilt overcurrent-protection...

[billi]

Let's hope the fuses are up to scratch! That lot will give a fair few kWhr in an instant if there is a short...

Modern batteries have pretty effective overcurrent protection! In fact this can be a problem with some inverters and smaller battery stacks. Charging the capacitors in the inverter trips the inbuilt overcurrent-protection...

Ohh , those modern batteries

[Stinsy]

Rather takes the "fun" out of installing batteries when a simple slip of a spanner can no-longer send a cloud of molten metal into your face!

[Tinbum]

For those with a Sofar ME3000 there is a firmware update available (3.06) for them for the US2000C, US3000C batteries that increases the settable DOD to 90%

[Stinsy]

For those with a Sofar ME3000 there is a firmware update available (3.06) for them for the US2000C, US3000C batteries that increases the settable DOD to 90%

You can go to 95% DoD on the “C” batteries!

[Tinbum]

Yes. The ME3000 was limited to 80% but is now 90 with the new firmware. I dont know why they didn't go to 95%.

[martinW]

With a max charge rate of 3kW (well a little less with losses) I suppose a sensible max storage capacity is going to be 30kWh anyway even on an E10 tariff. Mind with a 60kWh daily consumption WHAT would you be running????

Shame they don't do a 5kw version, I could run all my sockets on the critical load circuit...

Does anyone know if the critical load circuit will work with a load higher than 3kw when on Mains?
This is so I could run sockets on critical load circuit but manually don't run heavy loads when power outage happens? I can install washing machine and tumble drier on a different circuit no problem, but kettle (2kw) and toaster I can't. Cooker is gas so no worries there, just need to keep power on for controls.

Ideally I'd like Upstairs/downstairs lights, fridge/freezer and internet on the critical load circuit from the MS3000SP. Nice to have would be PC sockets and TV which are on the downstairs sockets circuit. Unfortunately, the kitchen sockets are ALSO on the downstairs sockets circuit and are not easy to move off.

Lights and fridge/freezer is easy to put on critical loads circuit(s), as is cooker (which is basically just a few watts for controls). Everything else means taking the house apart. She (who must not be name) would definitely not be amused.

Talking not being amused, I've just seen the price of:

Code of Practice for Electrical Energy Storage Systems, 2nd Edition

£65

[martinW]

just seen this 20 year warranty for the Sofar unit... not sure of terms but might be interesting


https://www.itstechnologies.shop/produc ... s=e&_v=1.0

[Oldgreybeard]

Let's hope the fuses are up to scratch! That lot will give a fair few kWhr in an instant if there is a short...

I just followed the instructions and fitted a 100A double fuse switch in the DC cables from the battery to the inverter. The batteries seem to have some sort of solid state switch as they turn on and off with no surge that I've been able to measure.

My plan for using the backup connection is to get new consumer units installed, splitting the house circuits into two parts, with a changeover contactor wired as shown in the SoFar manual. I've had a look at our downstairs ring main (from lots of photos I took before the house was plasterboarded inside) and the downstairs ring main looks as if it can be split into two halves, the kitchen and the rest of the house. We can manage without the kitchen being on the backup supply and that is where most of the big loads are.

I haven't yet discussed this with the electrician, but I think that it should be OK to have both the lighting circuits and the downstairs circuit (without the kitchen) connected to the backup power switched consumer unit, with the rest of the circuits contained within another consumer unit that is only ever power by the grid.